海相软土循环荷载下累积塑性应变试验研究

Experimental Study on Cumulative Plastic Strain of Marine Soft Soil under Cyclic Loading

文章针对软粘土累积塑性应变特征,进行了海相软粘土排水动三轴试验,分析了软土在循环荷载作用下累积塑性应变规律,探讨了饱和海相软土在不同荷载频率、不同围压以及不同动荷载作用下的累积塑性应变变化特征,构建了海相软土累积塑性变形模型。结果表明:低频荷载对软土变形有较大影响,软土累积塑性变形因荷载频率增加而减小,且初始应变受静偏应力的影响较大;根据试验结果拟合出海相软土变形发展规律的双曲线模型,揭示了软土在交通荷载作用下累积塑性变形规律。

In this paper,the drained dynamic triaxial test of marine soft soil is used to analyze the rule of cumulative plastic strain under cyclic loading.The variation characteristics of cumulative plastic strain of saturated marine soft soil under different loading frequencies,confining pressures and dynamic loads are discussed respectively,and a cumulative plastic deformation model of marine soft soil under cyclic load is built.The results show that the low-frequency load has a great influence on the deformation of soft soil,the cumulative plastic deformation of soft soil decreases with the increase of load frequency,and the initial strain is greatly affected by static deviator stress;based on the test results,the hyperbolic model of deformation development law of marine soft soil is fitted,and the cumulative plastic deformation law of soft soil under traffic load is revealed.